A short project that can be modified by other users. Once the code is uploaded, TM1637 will display 00:00, after that you can use the 4x4 keypad array to type how long the timer should go (4 digits should be pressesed, 5th press will trigger the countdown, you can press anything for the 5th one). You can use the function at the bottom of the code to modify the result once the timer ends.
Note: No code for the letters parts (outer right side of the 4x4 keypad) yet. bugs might be encountered when letters are used.
The HERO is a derivative of “Arduino UNO R3 Reference design” we just changed up a few things to make it our own. If you’re curious about what goes into our HERO board we published the open-source hardware files on our GitHub.
I cascaded four SN74HC595 shift registers to control 32 LEDs on 4 registers using 3 wires. I am adding a I2C 20×4 LCD screen to display the register and led values. I might add a standard 16×2 LCD screen to show up it is done.